About 93 percent of 3, 040 large U.S. hospitals used one or more day lighting or lighting conservation features, including tinted window glass (80 percent), reflective window glass (39 percent), external overhangs or awnings (47 percent), skylights or atriums designed to provide light (57 percent), automatic controls or sensors that increase or reduce lighting in response to the level of natural light (14 percent), and occupancy sensors that reduce lighting when rooms are unoccupied (46 percent).
Terahertz light - which lies between infrared light like that used by remote controls and the microwaves in the appliance of the same name - has become popular in scanning technology at airports and museums' back rooms because it can extract information without risk of damage.